Orthopaedics

Question 1

Benefits of regional anaesthesia for orthopaedic surgery

Answer 1

• Regional anaesthesia common, likely reduces risk of: o DVT/PE o Respiratory complications o Post-op pain, chronic pain syndromes. o Blood loss – reduced according to 17 RCTs (? By reducing venous pressure)

Question 2

ASRA guidelines on DVT prophylaxis and neuraxial blockade

Answer 2

o Administration of LMWH 6/24 post-op is effective and does not increase bleeding (Waiting 24/24 is less effective) o Continue 10 days at least, 28-35 if high risk. o Beware use of regional techniques: • LMWH→ Neuraxial block needs >12/24 • Therapeutic LMWH → Neuraxial needs >24/24 • LMWH→ Epidural removal needs >12/24, then wait >2/24 for next dose

Question 3

What are Gurd’s diagnostic criteria for fat embolism syndrome? During what sort of surgery does it occur?

Answer 3

• Complication of trauma and surgery on the femoral medulla - May be due to fat emboli, but the relationship is unclear (emboli universal, FES rare) • Fat emboli obstructing blood vessels – including Pulmonary HT, RHF and death • SIRS from emboli becoming free fatty acids o Treatment is supportive; intubate before respiratory failure Major features – at least one - Respiratory insufficiency - Cerebral involvement - Petechial Rash Minor features - at least 4 - Fever - Tachycardia - Jaundice - Renal - Retinal change Lab features - Fat microglobulinaemia (reqd) - Anaemia - Thrombocytopenia - ↑ ESR

Question 4

What is bone cement implantation syndrome?

Answer 4

Use of methylmethacrylate bone cement associated with a syndrome of hypoxia, hypotension and cardiovascular collapse.